Furnace



- W. M. DUNCAN.

FURNACE. APPLICATION man :uwzs. 1916.

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inventor: W. M. Duncan Patented Jan. 18, 1921.

W. M. DUNCAN.

FURNACE.

APPLICATION FILED JULY 29. IBIS.

Patented Jan. 18, 1921.

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inventor:-

W. M. Duman by fibh'r PAT T i OFFICE.

WILLIAM". M. DUNCAN, OF ALTON, ILLINOIS.

FURNACE.

Specification of Letters Patent.

Patented Jan. 18, 1921.

Application filed July 29, 1918. Serial No. 247,308.

T 0 all whom it may concern Be it known that I, VILLIAM M. DUNCAN, a citizen of the United States of America, a resident of Alton, in the county of Madison, State of Illinois, have invented Certain new and useful Improvements in Furnaces, of which the following is a full, clear, and exact description, reference being had to the accompanying drawings, forming a part of this specification.

My invention relates to improvements 1n furnaces, and more particularly to a furnace provided with a traveling grate, one of the objects being to produce an improved means for delivering fuel to the traveling grate.

In the preferred form of the invention, the fuel is admitted to the furnace through an intake chamber located at the rear lower portion of the combustion chamber at a point immediately above the rear portion of the traveling grate. The grate passes under the intake chamber at the rear of the furnace and carries the fuel toward the front of the furnace, the parts being so arranged that the hot gases passing from the fuel are directed backwardly, with respect to the movement of the grate. By constructing and arranging the parts in this manner, the traveling fuel will ignite and burn readily immediately after leaving the intake chamber, this being due to the fact that the flame and hot gases are directed toward the fresh fuel passing from the intake chamber.

A further object of the invention is to putduce a furnace of this kind wherein'the incoming fuel is delivered to the grate and distributed across the surface thereof, without being discharged through the outgoing gases passing from the combustion chamber.

Figure I is a longitudinal section of a furnace constructed in accordance with this invention.

Fig. II is a transverse section taken through the intake chamber, the grate being omitted.

The furnace herein shown is provided .with an endless traveling chain grate 1,

mounted between side frames 2. 3 designates tubular members whereby the side frames are connected to draft boxes 4, the

latter being provided with closures 4 which lie opposite to said tubular members 3. A natural draft, or forced draft, may be admitted through the draft boxes 4 and thence nace, so that the fresh fuel will be readily ignited by the fire on the traveling grate. The fuel is admitted .to the grate and uniformly distributed thereon, without being discharged through the current of hot gases at the rear of the furnace. The advantage of this lies in the fact that it is usually desirable to burn very fine coal on a grate of e kind herein shown. and if such fuel is ischarged through the outgoing gases, a large percentage of the fine particles of coal will be carried away by thedraft and deposited upon the boiler tubes 7 at the rear of the furnace.

The intake chamber 6 is therefore provided with a top wall 8, separated from the. ,top wall of the combustion chamber to prothe fuel is forced from said hopper, through the inlet opening 12 and discharged onto the fuel-receiving platform 13. It will be noted that this platform 13 is higher than the top of the traveling grate. 17 designates ablast device in the form of a steam pipe whereby the fuel is projected from the fuel-receiving platform and across the traveling grate. This steamipipe has a discharge nozzle 17' located in aplane between the inlet opening 12 and the platform 13. j

The screw conve or can be driven by any suitableimeans, an it will be readily under- The intake chamber 6 stood that a device of this kind can be driven at a predetermined speed with respect to 17 Although the steam blast may be powerful enough to project the fuel entirely across the grate, it cannot be used to distribute the fuel uniformly on the surface of the grate. To accomplish this result I preferably use a fuel distributing baffle 20, coir sisting of a pair of water-containing pipes arranged transversely of the traveling grate and located above the grate in a line between the intake chamber and the combustion chamber, so as to lie above and distribute the fuel passing from the intake chamber.

The screw conveyer can be operated to deliver the required amount of fuel to the platform 13, and the steam blast will quickly project all of this fuel across the grate. Thereafter the fuel will be carried forwardly under the fuel distributing baffle 20 and thence into the combustion chamber.

I claim:

1. A furnace provided with a combustion chamber, an intake chamber having an inlet- 'opening for the fuel, an endless traveling grate forming the bottom walls of said chambers, a fuel distributing baffle arranged transversely of said traveling grate and located above the grate in a line between said chambers so as to lie above and distribute the fuel passing from said intake chamber to said combustion chamber, means for delivering fuel to said inlet opening, and fuel projecting means comprising a blast device located below the discharge end of said delivery means whereby the incoming fuel is projected across the traveling grate in said intake chamber.

2. A furnace provided with a combustion chamber, an intake chamber having an inlet opening for the fuel, an endless traveling grate forming the bottom walls of said chamwhereby fuel is delivered bers, a fuel distributing baflle arranged transversely of said traveling grate and located above the grate in a line between said chambers so as to lie above and distributethe fuel passing from said intake chamber to said combustion chamber,"a screw conveyer into said inlet opening, and fuel projecting means comprising a steam pipe having a discharge nozzle immediately below the discharge end of said screw conveyer so as to project the incoming fuel across the traveling grate in said intake chamber.

3. A. furnace provided with a combustion chamber, an intake chamber having an inlet opening for the fuel, an endless traveling grate forming the bottom walls of said chambers, a fuel distributing baiile arranged transversely of said traveling grate and located above the grate in a line between said chambers so as to lie above and distribute the fuel passing from said intake chamber to saidcombustion chamber, a fuel-receiving hopper, a screw conveyerwhereby the fuel is fed from said hopper and through said inlet opening, a fuel-receiving platform located at one end of said intake chamber and below said inlet opening so as to receive the fuel discharged from said screw conveyer. said fuel-receiving platform being higher than the traveling grate, and a blast device whereby the fuel is projected from said fuelreceiving platform and across said traveling grate, said blast device comprising a discharge nozzle located below the discharge end of said screw conveyer in the plane between said inlet opening and said platform.

4. A furnace provided with a combustion chamber, an intake chamber having an inlet opening for the fuel, said intake chamber having a pair of spaced walls extending transversely of the combustion chamber and converging at their lower ends to form a restricted fuel opening, an endless traveling grate forming the bottom walls of said chambers, a fluid-containing fuel distributing bafile arranged transversely of said traveling grate below the end of one of said spaced intake chamber walls and located above the grate in a line between said chambers so as to lie above and distribute the fuel passingfrom said intake chamber to said combustion chamber, means for delivering fuel to said inlet opening, and a fuel projecting means comprising a blast device located below the discharge end of said delivery means whereby the incoming fuel is projected across the traveling grate within said restricted intake chamber. I

In testimon that I claim the foregoing I hereunto a it my signature.

WILLIAM M. DUNCAN. 

